Figure 4(d) Clear Floor Space in Alcoves. For a forward approach, where the depth of the alcove is equal to or less than 24 inches (610 mm), the required clear floor space is 30 inches (760 mm) wide by 48 inches (1220 mm) deep. For a parallel (side) approach, where the depth of the alcove is equal to or less than 15 inches (380 mm), the width is 30 inches (760 mm) and the length is 48 inches (1220 mm).